Previously, there is known a valve timing adjustment device that includes: a housing, which is rotated synchronously with a driving-side shaft of an internal combustion engine; and a cam plate, which is connected to a driven-side shaft. In this valve timing adjustment device, the housing and the cam plate are rotated relative to each other to adjust valve timing of valves of the internal combustion engine. For example, in the valve timing adjustment device of JP2009-185785A (corresponding to US2009/0199801A1), the housing is divided into two parts in an axial direction, and one of the housings, which is placed on the driven-side shaft side, has two external teeth arrangements that are configured to mesh with endless transmission members, respectively, which are wound around, for example, the driving-side shaft and/or the like. Furthermore, the other one of the housings, which is located on an opposite side that is opposite from the driven-side shaft, has a plurality of stoppers that are configured to limit the relative rotation between the housing and the cam plate in a predetermined range.